The agreements call for both to make improvements to current space at the airport. Sessions would be reimbursed for amenities totaling about $1 million that are the responsibility of the county, including the addition of taxiway and road to the hangars.

Under the lease agreement, Sessions and a company called Kilo Six would build three hangars on six acres. Two would be for private jets, but the larger space would house Sessions’ historic aircraft collection, which at one time has included an exotic Alpha Jet bomber trainer, an amphibious Beaver, a Grumman F8F military fighter, and a North American T-6 trainer used during World War II and the Korean conflict to train pilots.

Sessions has indicated to county staff members that he hopes to show the historic planes publicly, but Dave Waggoner, the airport’s director, said nothing has been put together yet in terms of a public program. Sessions declined to comment until the lease is approved.

It’s unclear when hangar construction might begin on the acreage, at the west side of the southern end of the runway, Waggoner said. But rent would be deferred for about seven years, at which point rent and fees would cost about $150,000 annually, according to the pending lease agreement. The lease would be for 40 years, with a 10-year option thereafter.

Regarding his collection, Allen has said that he likes the tie-in with the Future of Flight museum and the Boeing aircraft tour at Paine Field.

With a 10-year lease and options for 20 years, Allen is improving a 51,000-square-foot hangar at Paine Field at a cost of about $5.2 million. The county is reimbursing him about $2.2 million in rent credits. The annual lease is about $371,000.

Work on the hangar is under way and should be finished by fall, said Michael Nank, a spokesman for the collection.

“We’re looking at opening near the end of the year or the beginning of 2008,” Nank said. “But it will be quite an extensive move, as some of the planes can’t be flown there.”

The Flying Heritage Collection focuses mostly on World War II- and Cold War-era planes from around the world, including England, Japan, China and Russia.

Waggoner said both leases, as well as the other options at Paine Field and nearby, make for a better tourist attraction.

“We feel this is a very positive step to have the additional aviation attraction at the airport,” he said. “[Paine Field] is a tremendous place for aviation enthusiasts.”

Seattle Times business reporter Elizabeth Rhodes contributed to this report.